Is the following statement about neural networks overclaimed?
I think I would never say that neural networks are iterative methods. I would say that iterative methods (e.g. gradient descent) are used to train neural networks (which can be thought of as linear and non-linear models, but mainly non-linear), which is quite different. Maybe you should or wanted to say that deep learning is an area of study where iterative methods are used to train neural networks.

It is possible the reviewer is just telling you that this or similar statements have been used a lot and don't really provide any insight, they are misleading, or simply useless or trivial in the context of the paper or conference. 

Without further clarifications by the reviewer and about your paper and conference, it is difficult to provide more explanations.